I
developed this
outrigger sail boat
over the last 2 decades after I had a tri & a
cat -
then a traditional proa
with a outrigger float on it

a 23` & a 31`have proven themselfs
now
for over 4 winters sailing the strait of gibraltar & such in
bft 10 -
sailing off a beach with breaking waves so high as the boat is
wide -
then surfing back in & landing on the beach again -
anchoring with 1/4" nylon rode & a 5lbs anchor in a
white squall -
beating out off marina bay towards the west -
when the whole bay of gibraltar was white -
I have been so convinced of it now - that I have started a
88`already
-

the

idea

behind

the

concept

is

the

following

have a boat as long as possible for
comfort underway & anchoring -

because one can anchor almost anywhere
there is no need to go into a marina -

having good cruising speeds with as
little as possible of an sailarea - 1000sf / 88` - no need to
reef or change sails up to 8 bft - beating - 10 running - to be
safe from any breaking freak wave or gust

the

proa

today

modern proas can do a lot of things -
the polynesians could only dream about - the outriger sailboat
of
today - is non capsizeable - fast to change direction - safe to
manoever even in thight spots - can any time go on stand by - to
look around and see what`s going on - turn on the spot - like
with a twin engine power boat - to land on most beaches - leave
again - without turnig the boat - they
have
- once underway - no leeway it all - and all this - with a
boat - that weighs only one half of a catamaran - has only 2
small ruders - 360° - on the windward side of the mainhull - no
turning or moving mast - no dagger - center - steering boards -
nothing more to move or control - exept the sheets for the sails
-

general

requirements

for good performance - hard on the wind
- you need not only little resistence through the water - but
little aerodynamic resistence from the waterlinie on up as well
-
that is why the crew is seated inside the boat - ( 1 ) the
bridgedeck is aero dynamically shaped - ( 8 ) and up to about
30`
loa ( 13`wide ) because it is lighter then - one piece - can be
trailered high up -

sailing the proa - standing by -
changing directions

you are sitting broadside to the wind in your boat - the sails
are lose - you are drifting slowly to leeward - you pull on a
sheet - the boat moves in that direction - it`s that easy- with
the windward sail - ( 3 ) you even can turn on the spot - with
the main * you go to the right - with the windward sail to the
left - with the roller jibs ( 2 - these are just sails on a tube
on the stay - control line ( 2 ) going from the top of the tube
to the other - so if you pull one roller open - it closes the
other automatically ) you can make the boat fall away from the
wind - with the main sail you shot up to the wind - make the
boat
selfsteer -

* the main ( 5 ) ist on a mast with slides
to leeward - ( 4 )
so without having a turning mast - you have a clear flow on the
leeward side

steering is by 2 fin ruders - 45° on the
side of the main hull - ( 7 ) so you can beached most anywhere -
without damaging them - or having to pull them up - they are
controled by your feet -
slings in the lines going to the bell crank on the balanced
ruders - so they can turn which ever way they want to - left
& right - actually - you do not need them - because the boat
can be steered by itself - depending on the sail setting - exept
in large waves & swells it makes for a nicer - straiter
sailing - if you have the ruders - bow & stern -

the self leveling 2 stage fin -
( 6 )

sailforces + the windforces on the boat
combine to create a center of windforces somewhere 1/3 up the
mast - if now you have an angled fin to windward - you have a
means to counteracting these forces - you could put the fin to
leeward and lift the outrigger -
but
you would have the same problems as a trimaran - diagonal
capsize
in waves large enough - you would have very unstabil boat - like
it is very easy to hang up a pendulum - but try to stand it up
alone - further more - imagine a freak wave - hiting the boat
side ways - with the present setup - you have no wory it all - (
just make sure the structure holds up ) but the other setup is
doomed - before the wave even hits - that is why - in such
conditions - you do not want to let the wind & waves - be on
the wrong side - ever -

now - if the outrigger wants to come out of
the water - the fin`s lower part pulls it down - when the
outrigger wants to go down into the water - the upper part of
the
fin lowers the vector more to the horizontal - making the
outrigger want to come up - changes in bouancy of the fin helps
in each case - if - as some have told me - the fin would come
out
of the water - through wave dynamics - as it never has with this
configuration - then the center of lateral action moves
violently
forward - the boat shots up into the wind - I have tried this on
a model without the lower part of the fin on it -

we have now finished the design of a 2 mast proa -
it should even better selfsteer then the 1 mast version -
and can be totally sailed without the roller jib -
before the wind the forward mast sail can be sheeted
in a backward beating position -
because the jib is not needed in a storm it all -
it can be much larger for light air performance -
because they are on a stay 12° to leeward -
they do not back wind the mast sail -

--------------------------------- 2 mast proa

and here is a 3 mast version !

it has the same mast sail area as the 2 mast rig -

but a lower center of effort -

it seams this would be the choice on the larger boats -
it can have a cockpit on the bridgedeck -
or a long cockpit in lee with 2 steering stations